A controller includes at least one processor coupled to a memory storing instructions that, when executed by the at least one processor, cause the at least one processor to: determine a target engine outlet coolant temperature for a coolant in an engine system; determine an adjustment to a temperature of the coolant based on a determined engine inlet coolant temperature and the target engine outlet coolant temperature; and, alter a flow of the coolant by controlling a coolant valve in response to the determination of the adjustment to the temperature of the coolant.